Conventional chewing gums contain a synthetic resin base (e.g., styrene butadiene, isobutylene rubber, polyvinyl acetate) that softens at 50.degree.-60.degree. C., at which temperature the resin becomes sticky. The sticky resin is then formulated into a gum by admixture with sugar and other ingredients to saturate the sticky surfaces of the resin. The gum base represents approximately 20% of the dry weight of the final gum product, i.e, 15-30%, whereas the remainder of the gum is primarily sugar. Although the gum resin has been saturated with sugar, it still possesses adequate tack to stick to foil wrappers and other conventional gum packaging. In order to obviate the problem of package adherence, many techniques have been developed to provide a means for releasing and/or preventing adhesion between the sugared gum base and its packaging. For example, the gum base can be dusted with substances which have a higher molecular weight and are more hydrophobic than sugar, such as starch and other polysaccharides.
The protective coating only prevents adherence to a substrate prior to usage, however, extended chewing of the gum will release all of the entrapped sugar, thereby causing the gum base to return to its original degree of stickiness. The spent gum retains its stick property over a considerable period of time and is not biodegradable. Besides being nonbiodegradable, spent conventional gums can become imbedded into synthetic and natural fiber surfaces, such as furniture, clothing, carpets, sidewalks and hair. Removal of gum from such surfaces often requires use of highly toxic solvents (e.g., carbon tetrachloride) or Freon (to quick-freeze the gum) which is damaging to the ozone layer.
Thus, there remains a need for a chewing gum having a resin base that will not become sticky upon removal of its sugar component and which ultimately will not possess the sticky properties of conventional chewing gums from an environmental point of view.